Re: LSP Was: Mixing OO and DB

Daniel T. wrote:

> In article <fpmn2j$va9$1_at_aioe.org>, S Perryman <q_at_q.com> wrote:

>>Bob Badour wrote:

>>Here is the apocrypthal Circle/Ellipse problem as would be specified in >>Liskov/Wing notions :

> Oh snore. You explicitly define your types so you know they won't be
> substitutable and then... Surprise!

1. Don't be a fool Daniel. I have defined the types *exactly* how the aprocypthal example has been presented in debate for ages. So a straw-man argument there.
2. If you actually understand the Liskov/Wing definitions, then you will know that the Circle type is substitutable for Ellipse. But Circle is not a *Liskov/Wing* subtype of Ellipse.

Regards,
Steven Perryman Received on Sun Feb 24 2008 - 11:55:18 CET